Outer decking is a necessary part of an escalator or a moving walkway. The outer decking needs to be dismantled for easy replacement of parts during maintenance. There are several ways of securing the outer decking of an escalator or a moving walkway at present. One is that the outer decking 1′ is secured to a handrail system bracket 5′ by T-shaped bolts 12, see FIG. 6. When disassembling, the outer decking 1′ can be taken down only after the inner decking of handrail system is taken down first, even the skirting board needs to be taken down. Another is that the outer decking 1′ is mounted by side screws 13, see FIG. 7. In this case, if the escalator abuts against structure of building or a paratactic escalator, the outer decking 1′ can not be dismantled.